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Kyung-Taek Lim
10/01/00 07:40am

Version Number: 4.0.1.0
Platform: Windows 2000 Professional
Registered Name: Kyung-Taek_Lim
Organization: Brown
License ID: L2962-6007

My Mathematica has problem with user defined symbols.
I am not asking about numerical error.
I very often see that Mathematica is confused by user-defined symbols and give weird result. Here is an example.

One day, Plot worked or did not work depending on which user-defined symbol I used: ellf or elf. I have the nb file.

Today, I copied that nb file to a new nb file, and evaluated it. This time, Plot worked with both ellf and elf.

Why does Mathematica show such an inconsistant behavior with user defined symbols?
Is this caused by some incompatibility of Mathematica with Windows 2000?


Below is the nb file that depended on whether I used ellf or elf.

“I defined ellf to be a polynomial, and evaluated the cell.”

ellf underscript temp1 = Sqrt[Pi] Gamma [5/4] / Gamma [3/4] –( 7u^2 – (235/4)u^4 – 2325u^6 - (11515/2)u^8 + (4177761/20)u^10 - (108154285/24)u^12 + (1643081933/20)u^14)

Plot[ellf underscript temp1, {u,0.001,0.1}]
“graph plotted”
-Graphics-

“Now I defined elf to be the same polynomial, and evaluated the cell.”

elf underscript temp1 = Sqrt[Pi] Gamma [5/4] / Gamma [3/4] –( 7u^2 – (235/4)u^4 – 2325u^6 - (11515/2)u^8 + (4177761/20)u^10 - (108154285/24)u^12 + (1643081933/20)u^14)

Plot[elf underscript temp1, {u,0.001,0.1}]
Plot::plnr : elf underscript temp1 is not a machine-size real number at u = 0.001000004125`.
Plot::plnr : elf underscript temp1 is not a machine-size real number at u = 0.005016132165718664`.
Plot::plnr : elf underscript temp1 is not a machine-size real number at u = 0.009396071186077996`.
General::stop : Further output of Plot::plnr will be suppressed during this calculation.
“graph not plotted at all (only the axes shown)”
-Graphics-

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Subject (listing for 'inconsistant behavior with user defined symbols')
Author Date Posted
inconsistant behavior with user defined symbols Kyung-Taek Lim 10/01/00 07:40am
Re: inconsistant behavior with user defined sym... Forum Modera... 10/01/00 08:01am
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